Association Between Symptom Burden at Initiation of a Graduated Return to Activity Protocol and Time to Return to Unrestricted Activity After Concussion in Service Academy Cadets

Background: Current consensus and position statements recommend that concussed patients be asymptomatic upon the initiation of the graduated return to activity (RTA) protocol. However, a significant number of concussed patients are beginning their RTA protocols while endorsing symptoms. Purpose: To characterize symptom endorsement at the beginning of the RTA protocol and examine the association between symptom endorsement and RTA protocol duration in service academy cadets. Study Design: Cohort study; Level of evidence, 2. Methods: A prospective cohort study was conducted with cadets at 3 US service academies. Postconcussion symptom inventories were recorded upon the initiation of an RTA protocol. The Sport Concussion Assessment Tool Symptom Inventory was used to classify participants into 3 groups (0 symptoms, 1 symptom, and ≥2 symptoms) upon the initiation of the RTA protocol. The primary outcome of interest was RTA protocol duration. Kaplan-Meier survival estimates were calculated to estimate RTA protocol duration by symptom endorsement, sex, varsity status, academic break, and time to graduated RTA initiation. Univariate and multivariable Cox proportional hazards models were used to estimate the association between symptom endorsement at the initiation of the RTA protocol and RTA protocol duration (α < .05). Results: Data were analyzed from 966 concussed cadets (36% women). Headache (42%) and faintness/dizziness (44%) were the most commonly endorsed symptoms on the Sport Concussion Assessment Tool-Third Edition and the Brief Symptom Inventory-18, respectively. Univariate results revealed a significant association between endorsing ≥2 symptoms and RTA protocol duration. In the multivariable model, endorsing ≥2 symptoms maintained a statistically significant association with RTA protocol duration. Significant associations were observed between RTA protocol duration and nonvarsity status (27% longer), women (15% longer), academic breaks (70% longer), and time to the initiation of the RTA protocol (1.1% longer daily incremental increase) after controlling for covariates. Conclusion: Symptom endorsement at the initiation of an RTA protocol was associated with RTA protocol duration. Cadets who had returned to preinjury baseline symptom burden or improved from baseline symptom burden and endorsed ≥2 symptoms at the initiation of the RTA protocol took longer to RTA.

Exploring the Outcomes and Experiences of Black and White Athletes Following a Sport-Related Concussion: A Retrospective Cohort Study

ObjectiveYoung American athletes, at risk of sport-related concussion (SRC), represent many races, however, it is unknown how race influences the experience and outcome of SRC. Our objective was to compare White and Black athletes' recovery and subjective experiences after SRC.BackgroundNA.Design/MethodsA retrospective study was performed using the Vanderbilt Sport Concussion registry. Self-reported White (n = 211) and Black (n = 36) athletes (ages 12–23) treated for SRC between 2012 and 15 were included. Athletes with learning disabilities or psychiatric conditions were excluded. Data was collected by EMR review and phone calls to athletes and parents/guardians. The primary outcomes were: (1) days to symptom resolution (SR), (2) days to return-to-school, (3) changes in any daily activity (binary), (4) and sport behavior (binary). Secondary outcomes were changes in specific activities such as sleep, schoolwork, television time, as well as equipment (binary), playing style (more reckless, unchanged, less reckless) and whether the athlete retired from sport. Descriptive analyses, multivariable Cox proportional hazards and logistic regression were performed.ResultsA retrospective study was performed using the Vanderbilt Sport Concussion registry. Self-reported White (n = 211) and Black (n = 36) athletes (ages 12–23) treated for SRC between 2012 and 15 were included. Athletes with learning disabilities or psychiatric conditions were excluded. Data was collected by EMR review and phone calls to athletes and parents/guardians. The primary outcomes were: (1) days to symptom resolution (SR), (2) days to return-to-school, (3) changes in any daily activity (binary), (4) and sport behavior (binary). Secondary outcomes were changes in specific activities such as sleep, schoolwork, television time, as well as equipment (binary), playing style (more reckless, unchanged, less reckless) and whether the athlete retired from sport. Descriptive analyses, multivariable Cox proportional hazards and logistic regression were performed.ConclusionsRacial differences appear to exist in the outcomes and experience of SRC for young athletes, as Black athletes reached symptom resolution and return-to-school sooner than White athletes. Race should be considered as an important social determinant in SRC treatment.

Mixed Method Examination of the Brain Health of Former NCAA Division I Football Players and Former NFL Players

ObjectiveYoung American athletes, at risk of sport-related concussion (SRC), represent many races; however, it is unknown how race influences the experience and outcome of SRC. Our objective was to compare White and Black athletes' recovery and subjective experiences after SRC.BackgroundNA.Design/MethodsA retrospective study was performed using the Vanderbilt Sport Concussion registry. Self-reported White (n = 211) and Black (n = 36) athletes (ages 12–23) treated for SRC between 2012 and 15 were included. Athletes with learning disabilities or psychiatric conditions were excluded. Data was collected by EMR review and phone calls to athletes and parents/guardians. The primary outcomes were: (1) days to symptom resolution (SR), (2) days to return-to-school, (3) changes in any daily activity (binary), (4) and sport behavior (binary). Secondary outcomes were changes in specific activities such as sleep, schoolwork, television time, as well as equipment (binary), playing style (more reckless, unchanged, less reckless) and whether the athlete retired from sport. Descriptive analyses, multivariable Cox proportional hazards and logistic regression were performed.ResultsA retrospective study was performed using the Vanderbilt Sport Concussion registry. Self-reported White (n = 211) and Black (n = 36) athletes (ages 12–23) treated for SRC between 2012 and 15 were included. Athletes with learning disabilities or psychiatric conditions were excluded. Data was collected by EMR review and phone calls to athletes and parents/guardians. The primary outcomes were: (1) days to symptom resolution (SR), (2) days to return-to-school, (3) changes in any daily activity (binary), (4) and sport behavior (binary). Secondary outcomes were changes in specific activities such as sleep, schoolwork, television time, as well as equipment (binary), playing style (more reckless, unchanged, less reckless) and whether the athlete retired from sport. Descriptive analyses, multivariable Cox proportional hazards and logistic regression were performed.ConclusionsRacial differences appear to exist in the outcomes and experience of SRC for young athletes, as Black athletes reached symptom resolution and return-to-school sooner than White athletes. Race should be considered as an important social determinant in SRC treatment.

Concussion Assessment Across Several Clinical Batteries: Identifying the Components That Best Discriminate Injured Adolescents From Controls

ObjectiveTo identify which sub-components of 4 clinical assessments optimize concussion diagnosis.BackgroundMultiple assessments are part of the clinical toolbox for diagnosing concussions in youth, including the Post-Concussion Symptom Inventory (PCSI), the visio-vestibular exam (VVE), the King-Devick (KD) assessment, and the Sport Concussion Assessment Tool (SCAT-5). Most of these assessments have sub-components that likely overlap in aspects of brain function they assess. Discerning the combination of sub-components that best discriminate concussed adolescents (cases) from uninjured controls would streamline concussion assessment.Design/MethodsParticipants, 12–18 years, were prospectively enrolled from August 1, 2017 to April 29, 2020 Controls (n = 189, 53% female) were recruited from a suburban high school with PCSI, VVE, KD and SCAT-5 assessments associated with their sport seasons. Cases (n = 213, 52% female) were recruited from a specialty care concussion program, with the same assessments performed ≤28 days from injury. We implemented a forward-selection sparse principal component (PC) regression procedure to group sub-components into interpretable PCs and identify the PCs best able to discriminate cases from controls while accounting for age, sex, and concussion history.ResultsThe AUC of the baseline model with age, sex, and concussion history was 62%. The PC that combined all 5 sub-components of PCSI and SCAT-5 symptom count and symptom severity provided the largest AUC increase (+10.6%) relative to baseline. Other PC factors representing (1) KD completion time, (2) Errors in BESS tandem and double-leg stances, and (C) horizontal/vertical saccades and vestibular-ocular reflex also improved model AUC relative to baseline by 5.6%, 4.7%, and 4.5%, respectively. In contrast, the SCAT5 immediate recall test and right/left monocular accommodation did little to uniquely contribute to discrimination (<1% gain in AUC). Overall, the best model included 5 PCs (AUC = 77%).ConclusionsThese data show overlapping features of clinical batteries, with symptoms providing the strongest discrimination, but unique features obtained from neurocognitive, vision, and vestibular testing.

Longer Neurophysiological vs. Clinical Recovery Following Sport Concussion

Objectives: The objective of this study was to assess if injury-related alterations in the Sport Concussion Assessment Tool-5 (SCAT5) are matched by changes in transcranial magnetic stimulation-derived intracortical inhibition. We hypothesised that neurophysiological measures would take longer to return to normal than recovery assessed by the SCAT5 following sport related concussion (SRC).Methods: Thirteen male contact sport athletes (20.5 ± 4.5 years), who reported a concussion were recruited from local Rugby and American football clubs. Participants were tested at 4 timepoints throughout the concussion recovery period: within 24 h of concussion (day 0), and at 7, 9, and 11 days after concussion. All participants completed the SCAT5 and underwent TMS to assess cortical silent period duration (CSp), a measure of intracortical inhibition.Results: After concussion CSp significantly declined from day 0 (122 ± 28 ms) to day 11 (106 ± 15 ms) [F(3, 33) = 7.80, p &lt; 0.001]. SCAT5 measures of symptom number and severity were significantly decreased [symptom number: χ(3)2 = 30.44, p &lt; 0.01; symptom severity: χ(3)2 = 25.75, p &lt; 0.001] between the day 0 timepoint and each of the other timepoints. SCAT5 balance errors (mBESS) decreased significantly [F(3, 33) = 19.55, p &lt; 0.001] between the day 0 timepoint and each of the other timepoints. CSp and SCAT5 recovery patterns were different. SCAT5 domains recovered faster showing no further significant changes after day 7, whilst CSp was still decreasing between days 7 and 9. Due to the small sample size we also used a Bayesian linear model to investigate the recovery of CSp and mBESS. The posterior distribution of our Bayesian model provided evidence that CSp decreased at day 7 and it continued to decrease at day 9, unlike mBESS which decreased at day 7 and then reached a plateau.Conclusion: There are clinically important discrepancies between clinical and neurophysiological measures of concussion recovery. This finding has important implications for return to play (RTP) protocols and the prevention of complications after sport concussion.

Can Sport Concussion Assessment Tool (SCAT) Symptom Scores Be Converted to Rivermead Post-concussion Symptoms Questionnaire (RPQ) Scores and Vice Versa? Findings From the Toronto Concussion Study

Background: The Rivermead Post-Concussion Symptoms Questionnaire (RPQ) and the Sports Concussion Assessment Tool (SCAT) are widely used self-report tools assessing the type, number, and severity of concussion symptoms. There are overlapping symptoms and domains, though they are scored differently. The SCAT consists of 22 questions with a 7-point Likert scale for a total possible score 132. The RPQ has 16 questions and a 5-point Likert scale for a total of 80 possible points. Being able to convert between the two scores would facilitate comparison of results in the concussion literature.Objectives: To develop equations to convert scores on the SCAT to the RPQ and vice versa.Methods: Adults (17–85 years) diagnosed with a concussion at a referring emergency department were seen in the Hull-Ellis Concussion and Research Clinic, a rapid access concussion clinic at Toronto Rehab–University Health Network (UHN) Toronto Canada, within 7 days of injury. The RPQ and SCAT symptom checklists as well as demographic questionnaires were administered to all participants at Weeks 1, 2, 3, 4, 5, 6, 7, 8, 12, 16.Results: 215 participants had 1,168 matched RPQ and SCAT assessments. Total scores of the RPQ and the SCAT had a rho = 0.91 (p &lt; 0.001); correlations were lower for sub-scores of specific symptom domains (range 0.74–0.87, p &lt; 0.001 for all domain comparisons). An equation was derived to calculate SCAT scores using the number and severity of symptoms on the RPQ. Estimated scores were within 3 points of the observed total score on the SCAT. A second equation was derived to calculate the RPQ from the proportion weighted total score of the SCAT. This equation estimated corresponding scores within 3 points of the observed score on the RPQ.Conclusions: The RPQ and SCAT symptom checklists total scores are highly correlated and can be used to estimate the total score on the corresponding assessment. The symptom subdomains are also strongly correlated between the 2 scales however not as strongly correlated as the total score. The equations will enable researchers and clinicians to quickly convert between the scales and to directly compare concussion research findings.